Thermal cut-out device.



No. 800,821. PATENTBD OUT. 3, 1905. G. A. ROLFB.

THERMAL OUT-OUT DEVICE.

APPLICATION FILED JAN. 11. 1897. RENEWED JULY 27.1904.

' 2 SHEETS-SHEET 1.

'IIIIIIIIIIIIIlIIIIIIIIIIIIfiII/Illl YIIIIIIIIIIIIIIIIIIIIIIII No. 800,821. PATENTED OCT. 3, 1905. C. A. ROLFE.

THERMAL OUT-OUT DEVICE.

APPLICATION FILED JAN.11. 1897. RENEWED JULY 27,1904.

2 SHEETS-SHEET 2.

UNITED STATES PAlTEN OFFICE.

CHARLES A. ROLFE, OF ADRIAN, MICHIGAN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ROLFE ELECTRIC CO., OF ROCHESTER, NEIV YORK, A CORPORATION OF N ElV YORK.

THERMAL CUT-OUT DEVICE,

Specification of Letters Patent.

Patented Oct. 3, 1905.

To (LZZ whmn 71/; 712/01] concern:

Be it known that I, CHARLES A. RoLFn, a citizen of theUnited Statearesiding at Adrian, in the county of Lenawee and State of Michigan, have invented a certain new and useful Improvement in Thermal Cut-Out Devices, of which the following is afull, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to electrical-circuit protectors adapted to prevent damage to lowtension .circuits such as telephone, policetelegraph, fire-alarm, and the likeby unduly-strong currents intruding upon such circuits from high-tension circuits, such as power and lighting circuits.

Prominent objects of the invention are to provide a simple, practical, and inexpensive device of this kind, to arrange for the assembling of the same in a small space, to permit the easy and ready inspection of each device Without interfering with its condition, and to accomplish the above results in a simple and expeditious manner.

In the accompanying drawings, Figure l is a plan view of a device embodying my present invention. Figs. 2 and 3 are views of a portion of such device on an enlarged scale, Fig. 3 being a longitudinal section. Figs. i and 5 are views of parts of the device. Figs. 6 and 7 are views of a modified form of device, and Fig. 8 is a view of a detail of con- Struction.

Referring first to Figs. 1 to 5 inclusive, A is an insulating-base, which can be of any suitable material, such as ebonite, porcelain, or the like. This base is constructed with an elevated front strip a, which is provided with a socket a. A pair of line-contact springs B B are mounted on the base A on either side of the socket a. lontact posts or abutments 1 l are also mounted on the base A and arranged to cooperate with the line-springs B B. Binding-posts D D are mounted at the rear of the base A, and to these are connected the conductors C C. The posts D I) are in turn connected with the line-springs B B by conductors 3 3. A plug E is provided and arranged to fit into the socket a on the base A;

portion 0, adapted to fit in the socket a, an

insulating portion H, arranged within the conducting sleeve or portion 0, and a central insulating portion H, which extends through the insulating-sleeve H and is provided with a head it. The conducting-sleeve c is provided with a shoulder 0, adapted to fit against the abutment formed by the elevated strip a. The central conducting portion H is secured to the insulating-sleeve H by a screw M, as shown in Fig. 3. A collar L is secured by a pin Z to the rear portion of the conductingsleeve and a spring f" is arranged in the rear of the collar L and fitted over and against another collar f, which is arranged to slide over the conducting-sleeve c. This collar f" is provided with a pin f which guides it in a channel or slot 0" in the sleeve 0 and is constructed with a forward extension or prong f, which engages the loop K of a heat-coil device G. The latter consists, essentially, of a coil of fine wire 2", Fig. 5, embedded in a body or mass of wax G, which is engaged by a ring or eye 0, formed at the end of the sleeve 0. The ends of the fine-wire coil I are secured one to a screw N and the other to the screw M, so that the coil is connected on the one side to the central conducting portion H and on the other side to the conducting-sleeve 0. Over the entire forward portion of the plug thus described is arranged a tubular casing or sheath E. (Shown in Fig. 1.) \Vhen the plug E is in position in its socket, its end or tip h is in contact with the conducting strip or spring B and its sleeve 0 is in contact with the other conducting strip or spring B.

Under normal circumstances. the plug is as shown in the figures, in which case the circuit is closed from the conductors C C to the line-springs B B and the plug and its heatcoil device G. On the passage of an unduly strong current, however, the heat-coil I becomes heated, and thereby heats and softens or melts the body or mass of wax, so that the coil is freed from the wax and allowed to become separated therefrom. This permits the sliding sleevef to slide rearwardly on the plug, being impelled by the spring f so that it comes in contact with the abutment formed by the elevated portion a. Thereupon and on the continuation of this backward movement of said sleeve the plug is forced bodily forward and ejected from its socket, so that its rear end becomes separated from the linesprings B and B, thereby opening the circuit. lVhen it is desired to rearrange or rep'l'a'cefthe plug, a new heat-coil device is inserted in the eye 0 and connected with the prong f and the plug is again replaced in its socket.

It will be seen that the plug is not positively connected with the base at all, but is free therefrom, so that it can be withdrawn and replaced without interfering at all with its condition.

It will be understood that changes and modifications can be made without departing from the spirit of the invention.

hat I claim is 1. The combination with a circuit-breaking device, of ejecting means carried by said device for ejecting the same, substantially as described.

2. The combination with a base, of a circuitbreaking device, and means carried by said device for acting against the base so as to separate the device from the base, substantially as described.

3. The combination with a base provided with a socket, of a plug adapted to fit into said socket, and means carried by the plug for ejecting the same on the passage of an excess current, substantially as described.-

4. The combination with a base provided With a socket, of a plug adapted to fit into said socket, and means actuated by an excess current, and carried by the plug for projecting against the base so as to eject the plug, substantially as described.

5. The combination with a base provided with a socket, of a plug adapted to lit into said socket, line connections adapted to cooperate With the plug when in its socket, an excesscurrent device carried by the plug, and spring means also mounted on the plug and controlled by said excess-current device and arranged to eject the plug on the passage of an unduly strong current, substantially as described.

6. The combination with a base provided with a socket, of a plug adapted to [it into said socket, and means on the plug for ejecting the same, said means being disconnected from the base, whereby the plug is free to be removed at any time, substantially as described.

7. The combination with a base provided with a socket, of a plug constructed with two insulated conducting portions, line-contacts on the base adapted to cooperate with the two conducting portions of the plug, an excesscurrent device mounted on the plug, and means controlled by said excess-current device for ejecting the plug, also mounted thereon, substantially as described.

8. In a cut-out device for electric circuits, the combination of a circuit-breaking device adapted to open or break the circuit, means normally tending to actuate said device so as to cause it to break or open the circuit, and an excess-current-operated device holding said actuating means normally in engagement with the circuit-breaking device, and releasing the 'sam'eTviTen operated, substantially as set forth.

9. In a cut-out for electric circuits, the combination of a section of circuit-conductor arranged for bodily removal from the circuit, spring means normally tending to remove such section from the circuit, and connected with the same so as to be held under tension thereby, and an eXcess-current-operated device serving as a medium of connection between the circuit-breaking device and the spring means, and releasing the latter when operated so as to permit it to throw the section of circuit-conductor bodily out of circuit, substantially as set forth.

10. A thermal cut-out device for electric circuits, comprising a circuit-breaking device involvinga couple of insulated conducting members, a Wire connecting such members and arranged for heating a fusible body when an unduly-strong current passes over the line, and spring means arranged upon the circuit-breaking device and adapted for automatically throwing the same bodily out of circuit upon the fusion or softening of the fusible body, substantially as set forth.

11. A thermal cut-out device-comprising a circuit-breaking device arranged to be thrown bodily out of circuit, a spring-ejcctor constructed with a spring-actuated sliding member arranged to slide upon the circuit-breaking device and strike an abutment so as to throw the circuit-breaking device out of circuit, and means for permitting the springejector tooperate, substantially as set forth.

12. A thermal cut-out device for electric circuits, comprisinga circuit-breaking device for automatically opening the circuit, spring means supported upon the circuit-breaking device and arranged for throwing the latter bodily out of circuit, a fusible body and a wire section in part embedded in the fusible body and normally forming a portion of the circuit, said fusible body and wire section being both arranged upon the circuit-breaking device, and a connection between the fusible body and the spring when the latter is under tension, substantially as set forth.

13. The combination with suitable circuitcontacts, of a circuit-breaking device constructed with a couple of connecting members which engage with the circuit-contacts to close the circuit, a fusible body arranged upon the circuit-breaking device, a wire connecting the conducting members of the circuit-breaking device and in part embedded in the fusible body, a slide arranged upon the circuit-breaking device, spring resistance arranged between the slide and the fusible body, and a hook or loop partially embedded in the fusible body and connected with the slide when the latter is in position to maintain the spring under compression, substantially as set forth.

14. A thermal cut-out for electric circuits, comprising as a circuit-breaking device a plug constructed with a hollow conducting member inclosing another conducting member which is extended, whereby the two members can respectively engage separate contacts, and means for automatically throwing the plug out of circuit when an unduly-strong current passes over the line, substantially as set forth.

15. A thermal cut-out device for electric circuits, comprising the plug having a hollow cylindric conducting member inclosing a second conducting member insulated from the former, a spring-ejector arranged to slide upon the plug, a fusible body and a section of circuit-wire which serves to heat the latter when an unduly-strong current passes over the line, and aconnection between the fusible body and spring-ejector for holding the latter under compression when theplug is unfused, substantially as set forth.

16. A thermal cut-out for electric circuits, comprisingasliding plug composed of a couple of parallel conducting members insulated from one another, a fusible body held at the forward end portion of the plug, a spring-ejector arranged to slide upon the plug, means for connecting the fusible body with the springejector and normally holding the latter under compression, a conducting-section connecting the conducting members of the plug and partly embedded in the fusible body, a guide for the plug, and an abutment against which the spring-ejector acts when released, substantially as set forth.

17. The combination in a thermal cut-out device for electric circuits, of a plug for opening and closing the circuit, fixed and sliding collars on the plug, a spring between said collars, and means such as set forth for normally maintaining the spring under compression and for liberating the same when an unduly-strong current passes over the line, sul stantially as set forth. 7

18. In a protector for electric circuits, the combination with a removable circuit-controlling device, of means for actuating the same so as to control the circuit, said means being carried by the circuit-controlling device, and an eXcess-current-operated device also carried by the circuit-controlling device and arranged to hold the actuating means against operation, substantially as set forth.

19. In a protector for electric circuits, the combination of a removable circuit-controlling device, spring means tending to actuate said device so as to control the circuit, the said spring means being mounted upon the circuitcontrolling device, and an excess-current-operated device engaging the circuit-controlling device and holding the actuating means against operation, substantially as set forth.

20. In a protector for electric circuits, the combination of a removable circuit-breaking device, a spring mounted upon said device and engaging the same, an eXcess-current-operated device also mounted upon the circuitbreaking device and engaging the spring and the circuit-breaking device so as to hold the spring under compression, substantially as set forth.

21. In a protector for electric circuits, the combination of a circuit-breaking device arranged for ejection so as to open or break the circuit, a spring mounted upon the said device and arranged to eject the same, and an excesscurrent-operated device also mounted upon the circuit-breaking device and arranged to hold the spring under compression, substantially as set forth.

22. In a protector for electric circuits, the combination of a circuit breaking device adapted to remove a section of circuit-conductor bodily from the circuit, a spring mounted upon said device and adapted to eject the same so as to remove the section of conductor from circuit, and an excess-current-operated device also mounted upon the circuit-breaking device and arranged to hold the spring under compression, substantially as described.

CHARLES A. ROLFE.

\Vitnesses:

A. F. DURAND, MARGARET M. WAGNER. 

